AT89C5131A-RDTIL Atmel, AT89C5131A-RDTIL Datasheet - Page 157

• Manufacturer Part Number: AT89C5131A-RDTIL
• Description: IC 8051 MCU FLASH 32K USB 64VQFP
• Manufacturer: Atmel
• Series: AT89C513xr

Specifications of AT89C5131A-RDTIL

• Core Processor: C52X2
• Core Size: 8-Bit
• Speed: 48MHz
• Connectivity: I²C, SPI, UART/USART, USB
• Peripherals: LED, POR, PWM, WDT
• Number Of I /o: 34
• Program Memory Size: 32KB (32K x 8)
• Program Memory Type: FLASH
• Eeprom Size: 4K x 8
• Ram Size: 1.25K x 8
• Voltage - Supply (vcc/vdd): 3 V ~ 3.6 V
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 64-TQFP, 64-VQFP
• For Use With: AT89STK-10 - KIT EVAL APPL MASS STORAGEAT89STK-05 - KIT STARTER FOR AT89C5131
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Data Converters: -
• Other names: AT89C5131-RDTIL

ONCE Mode (ON
Chip Emulation)
4338F–USB–08/07
The ONCE mode facilitates testing and debugging of systems using AT89C5131A-L
without removing the circuit from the board. The ONCE mode is invoked by driving cer-
tain pins of the AT89C5131A-L; the following sequence must be exercised:
•
•
While the AT89C5131A-L is in ONCE mode, an emulator or test CPU can be used to
drive the circuit Table 111 shows the status of the port pins during ONCE mode.
Normal operation is restored when normal reset is applied.
Table 111. External Pin Status during ONCE Mode
Pull ALE low while the device is in reset (RST high) and PSEN is high.
Hold ALE low as RST is deactivated.
pull-up
Weak
ALE
PSEN
pull-up
Weak
Port 0
Float
Port 1
pull-up
Weak
Port 2
pull-up
Weak
Port 3
pull-up
Weak
Port I2
Float
XTAL1/2
Active
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